基于双模式探测器的大动态范围激光测距

Laser Ranging with Large Dynamic Range Based on Dual-Mode Detectors

开发了一种基于双模式探测的大动态范围激光测距方法.使用基于硅雪崩光电二极管（APD）的单个探测器在线性模式与盖革模式之间切换,实现了平均光子数为1~105的大动态强度范围光信号探测.在此基础上,进行了30m的室内线性探测模式测距和500m的室外盖革探测模式测距实验,利用时间相关单光子计数设备记录的信号详细分析了两种模式测距的时间特性,证明了这种方法可以根据探测距离和背景环境进行探测模式切换,从而实现大动态范围激光测距.并且进一步分析了APD偏置电压的调节对测距系统测量精度以及探测背景噪声的影响.

A new method of laser ranging is developed by employing a dual-mode photon detector to meet the large dynamic range of the echo photons.A single detector based on Si avalanche photodiode（APD）is operated between the linear mode and the Geiger mode by adjusting the bias voltage on APD and the detected dynamic range of the average photon number is 1~105 per pulse.The 30 m indoor and 500 m outdoor ranging experiments are carried out in the linear mode and the Geiger mode,respectively.The echo signal is recorded by a time correlated single photon counting equipment to investigate the ranging time characteristics in the dual-mode ranging system.The results indicate that the ranging system with a single detector can conveniently switch the operation mode to adapt to different ranging distances and environmental conditions and realize the large dynamic range detection.The measurement accuracy and the detection background noise are further studied while the operation modes are switched under different APD bias voltages.